(1.) Field of the Invention
In oil production, a by-product is often water. This is commonly disposed of by injecting it under pressure into a well. While injecting this water, a matter of concern is its quality. Among the parameters of interest are the amount of dispersed oil and the amount of solid particles in the water. These parameters affect the injectivity of the water into the well. Particles with sizes down to a few micrometres have been shown to have a negative influence on the injectivity.
(2.) Description of the Related Art
An existing device for monitoring oil particles in water is disclosed in International Patent Application Publication No. WO 00/46586 and is embodied in an analyser called ViPA developed by Jorin Limited, 4 Vulcan Close, Sandhurst, Berkshire, United Kingdom—see also the paper “On-line determination of particle size and concentration (solids and oil) using ViPA Analyser”, Dr Kami Nezhati, et al, presented at the “7th Annual International Forum Production Separation Systems”, 23 May 2000, Oslo. However, such an analyser uses a special measurement cell, requiring a side-stream in the overall process. Also, the analyser is not directly suitable for subsea operation.